Two of the great advantages of using a 12-Volt diaphragm pump technology in field marking operations are the relative ease and low cost of maintenance.
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The Shurflo 12-volt diaphragm pumps have been an industry standards in the boating, RV, restaurant, agricultural spraying industries for many years. As long as you are using water soluble materials then you'll have many hours of successful operations.

When replacement parts are needed the instructions for replacing the Shurflo 3.3 GPM Diaphragm and Valve Kits are straightforward with simple hand tools.

Please refer to the Shurflo Pump Repair and Inspection Instruction photo album to walk you through the maintenance steps. The 22 photos show the different parts of the pump.

Because field marking equipment use acrylic latex paint formulations it is almost impossible to remove all the paint residue during the clean-up process. Therefor the diaphragm pump will gradually accumulate paint material on the valve parts of the diaphragm pump. When the paint build-up becomes significant the pump performance will degrade which is observed by poor pump priming operations and lower pressure (narrowing of the paint spray fan at the spray tips).

We recommend that during the rinse cycle and also during storing between use and seasons that a "pump saver" or "pump protector" is incorporated. This material is diluted at 1-2 ounces per gallon of clean water and can remain in the unit without adverse impact. Maintaining a wet pump head will improve the pump priming and also will help residual paint to stay in suspension and get flushed during the next use.

The Shurflo 3.3 GPM no-flow control diaphragm pumps are used on the Model E-100 walk behind and the three RS-500 self-propelled rider field markers. The Model EZ-70 walk-behind field marker uses a smaller capacity 1.46 GPM Shurflo no-flow control 12-volt diaphragm pump.